The constant variable transmission allows operators to preset speeds and let the CVX Drive pick the most efficient range
RED DEER — Case IH’s Steiger high-horsepower tractors are more powerful than previous versions because of two new transmission offerings — A CVX Drive Series that includes a constant variable transmission, as well as a redesigned powershift transmission.
“We just introduced a new constant variable transmission that go in our tractors from 370 h.p. up to 540 h.p., with a peak horsepower of 605 h.p. This is the biggest CVT ever put into the articulated tractor,” said Mitch Kaiser of Case IH’s Steiger tractors during Agri-Trade in Red Deer.
Operators can set three preset speeds with the CVT and then the CVX Drive automatically selects the most efficient transmission range. The tractor will automatically make throttle and transmission adjustments to maintain the desired speed even in variable terrain.
“If you’re in the field with your air seeder and you want to set that speed exactly at say 4.7 m.p.h., it will maintain that speed going up a hill or going down a hill. So, you get the exact seed population you want,” Kaiser said.
Having the three preset speeds will come in handy when pulling a grain cart. One preset can be set as slow as three feet per minute for when uploading at the truck.
The second preset can be set for chasing the combine across the field, while the third preset can match exactly the speed of the combine.
Four planetary gear sets in the CVT overlap when speed is in-creased or decreased, which provide a seamless flow of power to the drive train and enables a strong incremental power growth and the torque needed to get through tough spots.
“You absolutely feel no shift shock, you also have a smoother transition and there is more power to the ground because you are never losing power when you shift from one gear to the next. By allowing you to do this, you get the perfect speed you need going through the field,” Kaiser said.
A split-throttle design allows operators the ability to fine tune the torque-to-r.p.m. ratio.
“Let’s say you’re pulling an air seeder, you want to set your outside lever right at 1,800 r.p.m. That gives you our full p.t.o. speed and full hydraulics, so you always have hydraulic flow to your fans. Then you set the inside one on the right forward so that it gives you full torque,” Kaiser said.
If a grower is pulling a big set of harrows, they will be able to run the r.p.m.’s lower while maintaining higher torque to find the fuel-efficient sweet spot.
Three sensitivity buttons in the cab for the CVT transmission allow operators to increase or decrease its response time.
Tractors with the CVX Drive come with an accelerator pedal so operators can easily control speeds when hooking up and performing tasks such as pushing or packing.
The CVX Drive with a CTV transmission is available in 17 different configurations including Quad-trac, Rowtrac, wheeled and scraper options.
For model year 2018, New Holland is offering the same CVT transmission in 10 tractors within its T9 series, including seven wheeled units, two of which are scrapers models, and three track tractors, said Ken Paul, marketing manager with New Holland.
Paul said the CVT transmission is operator friendly.
“You can put someone in this tractor and they will know how to drive it literally within a minute or two. Because the way that you move the machine forward, for example, is that you literally move the handle, the command grip inside the tractor, forward.”
He said the CVT transmission is a good option for growers who intend to use the tractor at very low speeds, or if they will be using it for transport or shuttling.
“For a scraper application they are very preferable, the reason again is like for tiling and water management type application you are going at a very slow rate speed,” Paul said.
There is a significant price difference between the CVT and powershift transmissions.
For New Holland tractors, in Canadian dollars farmers will see about a $50,000 list price difference between the two, said Paul.
But in the right application with a CVT transmission versus the power shift, over a three-year period you could see that pay for itself, he said.
In all Steiger tractors, the CVT transmissions sit on the same mounting and inside the same frame as the company’s powershift transmissions.
With the company’s redesigned PowerDrive powershift transmission, both Steiger Quadtrac and Steiger wheel tractors recently set records for fuel efficiency, the most horsepower to drawbar and the most pounds pulled at the drawbar at the Nebraska Tractor Test Laboratory.
“Our 620 wheel gives 37 more drawbar horsepower than a competitor 620 h.p. And our 620 h.p. Quadtrack gives up to 13 more h.p. to the drawbar than competitive tracked tractors,” Kaiser said.
The new powershift transmissions have two hydraulic pumps compared to just one pump in the previous version. One pump lubricates the transmission and controls the clutch lock up and disk connect.
“So, you have the connection of the clutch and the disconnection to give you more efficient oil flow to lock up the clutches in the transmission to transmit more efficient power to the drawbar,” Kaiser said.
Engine software changes help improve the engine’s ability to talk to the transmission software, which enables faster shifting.
“We went from six seconds to three seconds in forward to reverse mode, and a 20 percent faster shift in the forward gears so you get more efficiency and no lag in the transmission,” Kaiser said.
Splash pans were installed along the bottom gears in the transmission to keep oil from coming up around the gear train.
“Much like if you’re driving through a water puddle or water on the road. It slows your speed down. It takes power and it takes horsepower for you to do that. Where the new design does not allow this to do that in the Steiger transmission.”